Heat Exchanger

ABSTRACT

A heat exchanger includes a core and a header. At least one of first header portions or second header portions includes a guiding flow passage that has a plurality of flow passages which guide a fluid between a plurality of core end openings and a tank while changing a flow passage sectional shape.

TECHNICAL FIELD

The present invention relates to a heat exchanger, and particularly to aheat exchanger including a header which serves as an entrance or an exitof a fluid.

BACKGROUND ART

A heat exchanger including a header, which serves as an entrance or anexit of fluids is known in the related art. Such a heat exchanger isdisclosed in, for example, JP-UM-A-62-160173.

In JP-UM-A-62-160173, a plate-fin heat exchanger including a core, inwhich a plurality of first flow passages and a plurality of second flowpassages are alternately stacked to exchange heat between two types offluids, and a header, which serves as an entrance or an exit of thefluids, is disclosed. The core is formed in a shape in which a corner ofa rectangular parallelepiped is obliquely cut off, and a hollowtriangular prismatic header is formed in a triangular prismatic regioncorresponding to a cut off portion. The core has a uniform flow passagesectional shape as a whole. The header has a cylindrical port thatconnects the inside of the header to the outside and a hollow triangularprismatic tank. The plurality of first flow passages and the pluralityof second flow passages each branch off toward two end surfaces of thecore, which are obliquely inclined in opposite directions to each other,and each are open to another tank from each of the end surfaces to theinside. When the fluids flow in, the fluids are distributed torespective openings of the plurality of first flow passages or thesecond flow passages via the tanks of the respective ports.

PRIOR ART

Patent Document

[PTL 1] JP-UM-A-62-160173

SUMMARY OF THE INVENTION Problem to be Solved by the Invention

In the heat exchanger in JP-UM-A-62-160173, a plurality of openings ofthe first (second) flow passage units each have a horizontally-longrectangular shape when a flow passage section orthogonal to a flowdirection of a fluid is seen. The tank has a section formed as avertically long rectangular single flow passage covering a plurality ofopenings of the stacked first (second) flow passage units. In addition,the flow passage sectional area of the tank is significantly largecompared to the total area (total sectional area) of the openings of thefirst flow passages (second flow passages). That is, in the heatexchanger disclosed in JP-UM-A-62-160173, the flow passage sectionalshape significantly changes along the flow of a fluid at a boundaryportion between the core and the tank when the fluid passes through theheader. As a result, a problem that a pressure loss of a fluid when thefluid flows into the heat exchanger and flows out from the heatexchanger via the header becomes greater is caused by a significantchange in the flow passage sectional shape.

The invention is devised to solve such a problem described above, andone object of the invention is to provide a heat exchanger that cansuppress an increase in a pressure loss of a fluid when the fluid flowsinto the heat exchanger or flows out from the heat exchanger via aheader.

Means for Solving the Problem

To achieve the object, there is provided a heat exchanger of theinvention including a core that has a plurality of first flow passagesand a plurality of second flow passages and exchanges heat betweenfluids flowing in the first flow passages and the second flow passagesrespectively and a header that has a first header portion, which isconnected to an end surface of the core and covers core end openings ofthe plurality of first flow passages, and a second header portion, whichcovers core end openings of the plurality of second flow passages. Thefirst header portion and the second header portion each include a portfor causing the fluids to flow into or flow out from an inside thereofand a tank connected to the port. At least one of the first headerportion or the second header portion includes a guiding flow passagethat is connected to the plurality of core end openings of one of thefirst flow passages or the second flow passages and that has a pluralityof flow passages which extend to a corresponding tank side and guide thefluids between the plurality of core end openings and the tank whilechanging a flow passage sectional shape orthogonal to a flow directionof the fluids.

In the heat exchanger according to the invention, as described above, atleast one of the first header portion or the second header portion isprovided with a guiding flow passage that is connected to the pluralityof core end openings of one of the first flow passages or the secondflow passages and that has a plurality of flow passages which extend toa corresponding tank side and guide the fluids between the plurality ofcore end openings and the tank while changing a flow passage sectionalshape orthogonal to a flow direction of the fluids. Accordingly, theheat exchanger can set flow passage sectional shapes of the plurality offlow passages of the flow passage guiding units regardless of the flowpassage sectional shapes of the core end openings, and can guide thefluids between the tanks and the core via each of the flow passages. Forexample, the flow passage sectional shapes of the plurality of flowpassages of the flow passage guiding units can be changed to becomecloser to a flow passage sectional shape on the tank side as becomingcloser to the tank side. In addition, the flow passage sectional shapesof the flow passages of the flow passage guiding units can be changed tobecome closer to the shapes of the core end openings as becoming closerto the core end opening side. As a result, since a change in the flowpassage sectional shape between the core end openings of at least one ofthe first flow passages or the second flow passages and the header(tanks) can be made moderate, the heat exchanger can suppress anincrease in a pressure loss of a fluid when the fluid flows into theheat exchanger or flows out from the heat exchanger via the header. Inaddition, by the header being provided with the guiding flow passageshaving the plurality of flow passages, it is not necessary to provide aflow passage structure, of which the sectional shape changes, on thecore side. As a result, the heat exchanger can adopt the core having asimple shape, and can suppress the structure of the core becomingcomplicated.

In the heat exchanger according to the invention, preferably, theplurality of core end openings each have a first flow passage width in awidth direction orthogonal to a flow passage height direction, in asection orthogonal to the flow direction of the fluids. The tank has asecond flow passage width smaller than the first flow passage width inthe width direction, in a boundary portion of the tank with the guidingflow passage. The flow passages each have the flow passage sectionalshape which changes such that the closer to a core end opening side, thecloser a flow passage width becomes to the first flow passage width, andthe closer to the tank side, the closer the flow passage width becomesto the second flow passage width. When configured in such a manner, achange in the flow passage width between the header (tanks) and the coreend openings can be made moderate by changing the flow passage widths ofthe flow passages. As a result, the heat exchanger can suppress anincrease in the pressure loss caused by a sudden change in the flowpassage widths at the boundary portions between the header (tanks) andthe core end openings.

In the heat exchanger according to the invention, preferably, theplurality of core end openings each have a first flow passage height ina flow passage height direction, in a section orthogonal to the flowdirection of the fluids. The tank has a second flow passage heightlarger than the first flow passage height in the flow passage heightdirection, in a boundary portion of the tank with the guiding flowpassage. The flow passages each have the flow passage sectional shapewhich changes such that the closer to the core end opening side, thecloser a flow passage height becomes to the first flow passage height,and the closer to the tank side, the closer the flow passage heightbecomes to the second flow passage height. When configured in such amanner, a change in the flow passage height between the header (tanks)and the core end openings can be made moderate by changing the flowpassage heights of the flow passages. As a result, the heat exchangercan suppress an increase in the pressure loss caused by a sudden changein the flow passage heights at the boundary portions between the header(tanks) and the core end openings.

In the heat exchanger according to the invention, preferably, the flowpassages each are formed such that a ratio between a flow passage widthand a flow passage height of the flow passage sectional shape is changedwhile a flow passage sectional area is kept substantially constant inthe flow direction of the fluids. When configured in such a manner, evenin a case where the flow passage widths or the flow passage heights ofthe flow passages are changed according to the shapes of the core endopenings and the flow passage sectional shapes on the tank side, it isnot necessary to change the flow passage sectional area of each of theflow passages to become larger. As a result, the heat exchanger cansuppress an increase in the pressure loss caused by a change in the flowpassage sectional areas of the flow passages.

In the heat exchanger according to the invention, preferably, the firstheader portion and the second header portion are integrally provided inthe common header. The guiding flow passage includes a first guidingflow passage having the plurality of flow passages for guiding thefluids flowed into or flowed out from the plurality of first flowpassages and a second guiding flow passage having the plurality of flowpassages for guiding the fluids flowed into or flowed out from theplurality of second flow passages. When configured in such a manner, theheader can be used in common by providing the first guiding flow passageand the second guiding flow passage corresponding to the first flowpassages and the second flow passages respectively in the header even ina case where both of the core end openings of the first flow passagesand the core end openings of the second flow passages are formed in thecommon end surface of the core. As a result, since the internal volumeof the header can be decreased, the heat exchanger can suppress thetotal weight (wet weight) of the heat exchanger, in particular, in acase where a liquid fluid is used compared to a case where the firstflow passages and the second flow passages are separately provided inthe header. This is particularly useful for a heat exchanger used inapplication of strict weight limits of an aircraft. In addition, even ina case where the header of the first flow passages and the second flowpassages is used in common, the suppression of a pressure loss can beachieved by changing the flow passage sectional shapes of the respectiveflow passages of the first guiding flow passages and the second guidingflow passages.

In the heat exchanger according to the invention, preferably, the coreend openings of the first flow passages and the core end openings of thesecond flow passages each include a plurality of entrance openings and aplurality of exit openings formed in the end surface of the core. Theguiding flow passage provided in at least one of the first headerportion covering the first flow passages or the second header portioncovering the second flow passages includes an entrance guiding flowpassage corresponding to the plurality of entrance openings and an exitguiding flow passage corresponding to the plurality of exit openings.When configured in such a manner, even in a case where both of theentrance openings and the exit openings are formed in the common endsurface of the core, the header 2 can be used in common due to theentrance guiding flow passage and the exit guiding flow passagecorresponding to the entrance openings and the exit openingsrespectively. As a result, since the internal volume of the header canbe decreased, the heat exchanger can suppress the total weight (wetweight) of the heat exchanger, in particular, in a case where a liquidfluid is used compared to a case where the header is separately providedfrom the entrance openings and the exit openings. In addition, even in acase where the header is used in common, the heat exchanger can achievethe suppression of a pressure loss by changing the flow passagesectional shapes of the respective flow passages of the entrance guidingflow passages and the exit guiding flow passages.

In the heat exchanger according to the invention, preferably, the corehas a stacked structure in which the plurality of first flow passagesand the plurality of second flow passages are alternately stacked in aheight direction via partition plates. An edge of the header is joinedto an edge of the end surface of the core. Respective bulkheads of theplurality of flow passages of the header are joined to core end surfaceportions of the partition plates between the first flow passages and thesecond flow passages. The word “join” in the invention is a concept thatincludes not only integrally fixing the core to the header, which areseparately provided, by means of welding, brazing, and other methods butalso integrally fixing (forming) the header to the core by directlyforming (modelling) a structure portion configuring the header withrespect to the end surface of the core. When configured as describedabove, the core and the header can be joined not only to the edges butalso to an outer surface where the core end openings (core end surfaceportions of the partition plate) are not formed, in the end surface inwhich the core end openings are formed. As a result, since a joiningarea can be increased and a region between both ends of the end surfaceof the core in a direction in which the partition plates extend can beset as a joining region, the heat exchanger can effectively improve thejoining strength of the core and the header. In addition, since thepressure resistance performance of the header can be improved with theimprovement of the joining strength and the degree of freedom ofinternal structure of the header can be enhanced, the heat exchanger caneasily optimize the shapes of the flow passages and the tanks of theheader.

In the heat exchanger according to the invention, preferably, the corehas a rectangular parallelepiped shape, and the respective core endopenings of the plurality of first flow passages and the plurality ofsecond flow passages are vertically arranged in the end surface formedof any one of side surfaces of a rectangular parallelepiped. The headeris joined to the end surface so as to integrally include the firstheader portion and the second header portion and to collectively coverthe respective core end openings of the plurality of first flow passagesand the plurality of second flow passages. When configured in such amanner, it can be suppressed that the structure of the core becomescomplicated since the core can be formed in a rectangular parallelepipedshape just as a general stacked heat exchanger. In addition, since theflow passages of the guiding flow passages can distribute (guide) afluid to the first flow passages and the second flow passages, it is notnecessary to form the respective core end openings of the plurality offirst flow passages and the plurality of second flow passages atpositions separated away from each other in order to mount anotherheader. As a result, the heat exchanger can simplify the structure ofthe core.

Effect of the Invention

According to the invention, as described above, an increase in apressure loss of a fluid when the fluid flows into the heat exchanger orflows out from the heat exchanger via the header can be suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating a heat exchanger according toone embodiment of the invention.

FIG. 2 is a horizontal sectional view illustrating a first flow passageof the heat exchanger according to the embodiment of the invention.

FIG. 3 is a horizontal sectional view illustrating a second flow passageof the heat exchanger according to the embodiment of the invention.

FIG. 4 is a view illustrating an end surface of a core.

FIG. 5 is an enlarged perspective view schematically illustrating ahorizontal section of a header.

FIG. 6 is a view schematically illustrating a section taken along500-500 line of FIG. 3.

FIG. 7 is a view illustrating a core side end portion of the header.

FIG. 8 is a view schematically illustrating a section taken along600-600 line of FIG. 6.

FIG. 9 is an enlarged sectional view illustrating an enlarged internalstructure of the header in FIG. 6.

FIG. 10 is a schematic view conceptually illustrating a shape of a flowpassage.

FIG. 11 is a schematic view illustrating a modification example in whicha heat exchanger is provided with a mixing header.

MODES FOR CARRYING OUT THE INVENTION

Hereinafter, an embodiment of the invention will be described based onthe drawings.

First, a configuration of a heat exchanger 100 according to theembodiment will be described with reference to FIGS. 1 to 10. In theembodiment, an example of a plate-fin heat exchanger will be described.In addition, an example of a heat exchanger that is mounted on anaircraft and exchanges heat between fuel for an aircraft and oil for anaircraft (lubricating oil) will be described in the embodiment.

(Overall Configuration of Heat Exchanger)

As illustrated in FIG. 1, the heat exchanger 100 includes a core 1, aheader 2, and a header for U-turn flow 3.

The core 1 includes a plurality of first flow passages 1 a in which fuel4 flows and a plurality of second flow passages 1 b in which oil 5flows. The core 1 is configured to exchange heat between the fuel 4flowing in the first flow passages 1 a and the oil 5 flowing in thesecond flow passages 1 b. Both of the fuel 4 and the oil 5 are examplesof “fluids” in the Claims. For convenience of description, the firstflow passages 1 a and the second flow passages 1 b are illustrated withdifferent hatching in FIG. 1.

The core 1 has a stacked structure in which the plurality of first flowpassages 1 a and the plurality of second flow passages 1 b arealternately stacked in a height direction (Z-direction). The core 1 hasa rectangular parallelepiped shape. In the embodiment, the header 2 isprovided on an end surface 11 which is on one side (X1-direction side)in a longitudinal direction of the core 1. The header for U-turn flow 3is provided on an end surface which is on the other side (X2-directionside) in the longitudinal direction of the core 1.

The header 2 is connected to the end surface 11 of the core 1, and is acollecting and distributing unit which serves as an entrance or an exitof a fluid with respect to the core 1. In the embodiment, the header 2has a function of causing the fuel 4 to flow into (distribute) and flowout from (collect) the respective first flow passages 1 a. In addition,the header 2 has a function of causing the oil 5 to flow into(distribute) and flow out from (collect) the respective second flowpassages 1 b.

The header for U-turn flow 3 is connected to a side surface of the core1 on the opposite side to the header 2. The header for U-turn flow 3 hasa function of causing fluids (fuel 4 and oil 5), which have flowed fromthe header 2 and passed through the core 1, to make a U-turn in areverse direction (direction of the header 2) and to flow into the core1 again.

The heat exchanger 100 can be provided, for example, in an aircraft.After exchanging heat with the oil 5 in the heat exchanger 100, the fuel4 is supplied to an engine. After being supplied to a lubricatingportion (sliding portion) of the engine of the aircraft, the oil 5 isintroduced into the heat exchanger 100. After exchanging heat with thefuel 4, the oil 5 returns to an oil tank. As a result, in the heatexchanger 100, the fuel 4 is preheated and heat absorbed by the oil 5 isdischarged by the engine being lubricated and heat being exchangedbetween the oil 5 which absorbed heat and the fuel 4.

(Core)

Referring back to FIG. 1, the core 1 is configured by alternatelystacking the plurality of first flow passages 1 a and the plurality ofsecond flow passages 1 b via tube plates 12. The tube plates 12 areexamples of a “partition plate” in the Claims. Side plates 13 areprovided at both ends of the core 1 in a stacking direction(Z-direction), respectively. Hereinafter, the stacking direction of thefirst flow passages 1 a and the second flow passages 1 b will bereferred to as the Z-direction, a direction (side where there is the endsurface 11) where the header 2 is provided with respect to the core 1will be referred to as an X-direction, and a direction orthogonal to theX-direction and the Z-direction will be referred to as a Y-direction.

The first flow passages 1 a and the second flow passages 1 b are hollowplates sandwiched between the tube plates 12. The tube plates 12function as primary heat transfer surfaces for heat exchange. The tubeplates 12 are formed of plate-shaped members each having high thermalconductivity and a small thickness.

As illustrated in FIGS. 2 and 3, the respective first flow passages 1 aand the respective second flow passages 1 b have substantially the samestructure. The first flow passages 1 a and the second flow passages 1 bare defined by the tube plates 12 in the Z-direction and side bars 16,which are both end portions in the Y-direction and are sandwichedbetween the tube plates 12. The first flow passages 1 a and the secondflow passages 1 b linearly extend in the X-direction. RespectiveX1-direction side end portions and X2-direction side end portions of thefirst flow passages 1 a and the second flow passages 1 b are open. Coreend openings 14 a and 14 b, which are open to the outside from the endsurface 11 of the core 1, are formed in the X1-direction side endportions of the first flow passages 1 a and the second flow passages 1b, respectively. Respective openings for U-turn flow 17, which are opento the outside from the opposite end surface of the core 1, are formedin the X2-direction side end portions of the first flow passages 1 a andthe second flow passages 1 b.

In addition, the first flow passages 1 a and the second flow passages 1b each are partitioned into a Y1-side and a Y2-side with a partitioningmember 18 disposed in the center in the Y-direction. The partitioningmembers 18 extend from the X1-direction side end portions to theX2-direction side end portions. The partitioning members 18 partitioneach of the core end openings 14 a of the first flow passages 1 a andthe core end openings 14 b of the second flow passages 1 b into entranceopenings 15 a and exit openings 15 b. Similarly, the openings for U-turnflow 17 of the first flow passages 1 a and the second flow passages 1 beach have an exit portion 17 a and an entrance portion 17 b, which aredefined by the partitioning members 18.

As illustrated in FIG. 4, in the core 1, the core end openings 14 a ofthe plurality of first flow passages 1 a and the core end openings 14 bof the plurality of second flow passages 1 b are vertically arranged inthe end surface 11 (refer to FIG. 4) which is a rectangularparallelepiped side surface. In the embodiment, the respective core endopenings (entrance openings 15 a and exit openings 15 b) of the firstflow passages 1 a and the second flow passages 1 b have substantiallythe same sectional shape (opening shape). That is, each of the pluralityof core end openings 14 (entrance openings 15 a and exit openings 15 b)has a flow passage width W1 in a width direction (B-direction)orthogonal to a flow passage height direction (A-direction), in asection orthogonal to a flow direction of a fluid. The flow passagewidth W1 is an example of a “first flow passage width” in the Claims. Inaddition, each of the plurality of core end openings 14 (entranceopenings 15 a and exit openings 15 b) has a flow passage height H1 inthe flow passage height direction (A-direction), in the sectionorthogonal to the flow direction of a fluid. The flow passage height H1is an example of a “first flow passage height” in the Claims. The coreend openings 14 (entrance openings 15 a and exit openings 15 b) each areformed in a horizontally-long rectangular shape such that the flowpassage width W1 is larger than the flow passage height H1.

As illustrated in FIGS. 2 and 3, respective corrugated fins 19 areprovided along circulation paths from the entrance openings 15 a to theexit openings 15 b inside the first flow passages 1 a and the secondflow passages 1 b. Although the corrugated fins 19 are provided over theentire paths of the first flow passages 1 a and the second flow passages1 b, the corrugated fins are partially illustrated at several places ofthe first flow passages 1 a for convenience of illustration in FIGS. 2and 3. In addition, the illustration of the corrugated fins 19 isomitted in each drawing other than FIGS. 2 and 3. The corrugated fins 19function as secondary heat transfer surfaces of the first flow passages1 a.

The core 1 is a counter-flow core in which the flow of the fluid (fuel4) flowing in the first flow passages 1 a and the flow of the fluid (oil5) flowing in the second flow passages 1 b are opposed to each other inreverse directions. That is, fuel flows into the first flow passages 1 a(refer to FIG. 2) from the entrance openings 15 a on a Y1-directionside, and flows in an X2-direction. After then, the fuel makes a U-turnto a Y2-direction side via the openings for U-turn flow 17, and flowsout from the exit openings 15 b on the Y2-direction side. After flowinginto the second flow passages 1 b (refer to FIG. 3) from the entranceopenings 15 a on the Y2-direction side and flowing in the X2-direction,the oil makes a U-turn to the Y1-direction side via the openings forU-turn flow 17 and flows out from the exit openings 15 b on theY1-direction side.

(Header)

As illustrated in FIG. 1, the header 2 is provided to cover the endsurface 11 on the X1-direction side of the core 1. The header 2 isprovided to cover the entire surface of the rectangular end surface 11(refer to FIG. 4). The header 2 covers each of the core end openings 14a (entrance openings 15 a and exit openings 15 b) of the first flowpassages 1 a and the core end openings 14 b (entrance openings 15 a andexit openings 15 b) of the second flow passages 1 b.

Specifically, the header 2 includes header portions 21 a and 21 b (referto FIG. 2) covering the core end openings 14 a of the plurality of firstflow passages 1 a and header portions 21 c and 21 d (refer to FIG. 3)covering the core end openings 14 b of the plurality of second flowpassages 1 b, as illustrated in FIG. 5. Both of the header portions 21 aand 21 b are examples of a “first header portion” in the Claims. Both ofthe header portions 21 c and 21 d are examples of a “second headerportion” in the Claims.

As illustrated in FIGS. 2 and 5, the header portion 21 a covers theentrance openings 15 a, out of the core end openings 14 a of the firstflow passages 1 a. The header portion 21 b covers the exit openings 15b. The header portions 21 a and 21 b function as an inlet and an outletof the fuel 4, respectively, with respect to the plurality of first flowpassages 1 a. As illustrated in FIG. 3, the header portion 21 c coversthe entrance openings 15 a, out of the core end openings 14 b of thesecond flow passages 1 b. The header portion 21 d covers the exitopenings 15 b. The header portions 21 c and 21 d function as an inletand an outlet of the oil 5, respectively, with respect to the pluralityof second flow passages 1 b.

As illustrated in FIG. 5, the two header portions 21 a and 21 b on afirst flow passage 1 a side and the two header portions 21 c and 21 d ona second flow passage 1 b side are integrally provided in the common(single) header 2, in the embodiment. In total, four header portions (21a, 21 b, 21 c, and 21 d) are spaces isolated from each other by an innerwall portion of the header 2. The four header portions (21 a, 21 b, 21c, and 21 d) are arranged along the end surface 11 of the core 1 in theY-direction. As described above, in the embodiment, the header 2integrally includes the four header portions (21 a, 21 b, 21 c, and 21d), and is joined to the end surface 11 so as to collectively cover therespective core end openings 14 (14 a and 14 b) of the plurality offirst flow passages 1 a and the plurality of second flow passages 1 b.

As described in FIGS. 2 and 3, the header portions (21 a, 21 b, 21 c,and 21 d) each include a port 22 for causing a fluid to flow into orflow out from an inside thereof and a tank 23 connected to the port 22.That is, the two header portions 21 a and 21 b each include a port 22 aand a tank 23 a. The two header portions 21 c and 21 d each include aport 22 b and a tank 23 b. In addition, in the embodiment, the headerportions (21 a, 21 b, 21 c, and 21 d) each include a guiding flowpassage (24 a, 24 b, 24 c, and 24 d) connecting the plurality of coreend openings 14 to the tank 23. In each of the header portions 21 a, 21b, 21 c, and 21 d, the port 22, the tank 23, and the guiding flowpassage 24 are integrally formed. The guiding flow passage 24 a is anexample of a “first guiding flow passage” and an “entrance guiding flowpassage” in the Claims. The guiding flow passage 24 b is an example ofthe “first guiding flow passage” and an “exit guiding flow passage” inthe Claims. The guiding flow passage 24 c is an example of a “secondguiding flow passage” and the “entrance guiding flow passage” in theClaims. The guiding flow passage 24 c is an example of the “secondguiding flow passage” and the “exit guiding flow passage” in the Claims.

<Port>

As illustrated in FIG. 1, the ports 22 (22 a and 22 b) have asubstantially circular tubular shape, and are configured as connectingportions that fluidically connect the heat exchanger 100 to an externalpipe (not illustrated). The ports 22 a and 22 b have flow passage widthsW2 a and W2 b smaller than the flow passage width W1 in the widthdirection (B-direction), respectively (W2 a and W2 b<W1). The ports 22 aand 22 b have flow passage heights H2 a and H2 b larger than the flowpassage height H1 in the flow passage height direction (A-direction),respectively (H2 a and H2 b>H1).

Since the ports 22 a and 22 b have a substantially circular tubularshape in the embodiment, the flow passage width W2 a (W2 b) and the flowpassage height H2 a (H2 b) are the same and match the inner diameters ofthe ports 22 a (21 b), respectively. The ports 22 a each have an innerdiameter larger than those of the ports 22 b (W2 a>W2 b, and H2 a>H2 b).

In total, four ports 22 (22 a and 22 b) are disposed to be separatedaway from each other so as not to interfere the external pipe. That is,two ports 22 a (entrance side and exit side) are disposed to beseparated away from each other in the Z-direction at a center side ofthe header 2 in the Y-direction. Two ports 22 b (entrance side and exitside) are disposed at each end portion side of the header 2 in theY-direction so as to be separated away from each other in theZ-direction.

<Tank>

As illustrated in FIGS. 5 and 6, the tanks 23 (23 a and 23 b) are spaceportions extending in the Z-direction, and are gathering portions forfluids flowing between the ports 22 and the respective core end openings14 (entrance openings 15 a or exit openings 15 b). Although only alongitudinal section passing through the tank 23 b is illustrated inFIG. 6, the tanks 23 a have the same basic structure as the tanks 23 b.The tanks 23 are connected to the ports 22 on the X1-direction side andare connected to the guiding flow passages 24 on the X2-direction side.The tanks 23 each are formed such that a flow passage height in theZ-direction becomes larger as facing toward a guiding flow passage 24side. The tanks 23 each are formed such that a flow passage heightsmoothly increases from a port 22 side to the guiding flow passage 24side. In addition, a boundary portion between an inside surface of eachtank 23 and an inside surface of each port 22 is formed to be a curvedsurface that continues smoothly (edge is not formed).

In the boundary portions of the tanks 23 with the guiding flow passages24, the tanks 23 a and 23 b have flow passage widths W3 a and W3 b(refer to FIGS. 2 and 3) smaller than the flow passage width W1,respectively (W3 a and W3 b<W1). The flow passage width W3 a (W3 b) hasa direction along a flow passage end surface 251, which is an endsurface of each guiding flow passage 24, as a width direction. Both ofthe flow passage widths W3 a and W3 b are examples of a “second flowpassage width” in the Claims. In addition, in the boundary portions ofthe tanks 23 with the guiding flow passages 24, the tanks 23 each have aflow passage height H3 (refer to FIG. 6) larger than the flow passagewidth W1 (H3>H1). The flow passage height H3 has the Z-direction as aheight direction. The flow passage height H3 is an example of a “secondflow passage height” in the Claims.

<Guiding Flow Passage>

As illustrated in FIGS. 5 and 6, the guiding flow passages 24 (24 a, 24b, 24 c, and 24 d) are connected to the plurality of corresponding coreend openings 14 and extend to corresponding tank 23 sides. The guidingflow passages 24 are disposed on core 1 side end portions (X2-directionside end portions) of the header 2, and communicate with the tanks 23 onthe X1-direction side. In the embodiment, the guiding flow passages 24have a plurality of flow passages 25 (25 a and 25 b) guiding a fluidbetween the plurality of core end openings 14 and the tank 23. Theguiding flow passages 24 have a function of guiding a fluid such thatthe flow of the fluid between the plurality of core end openings 14 andthe tank 23 becomes smooth.

Specifically, as illustrated in FIG. 2, the guiding flow passages 24 aand 24 b of the header portions 21 a and 21 b connected to the firstflow passages 1 a have the plurality of flow passages 25 a (refer toFIG. 5) for guiding the fuel 4 flowing into or flowing out from each ofthe plurality of first flow passages 1 a. As illustrated in FIG. 3, theguiding flow passages 24 c and 24 d of the header portions 21 c and 21 dconnected to the second flow passages 1 b have the plurality of flowpassages 25 b (refer to FIG. 5) for guiding the oil 5 flowing into orflowing out from each of the plurality of second flow passages 1 b. Thatis, the plurality of respective flow passages 25 a of the guiding flowpassages 24 a and 24 b are connected to the core end openings 14 a(refer to FIG. 4) of the first flow passages 1 a. In addition, theplurality of respective flow passages 25 b of the guiding flow passages24 c and 24 d are connected to the core end openings 14 b (refer to FIG.4) of the second flow passages 1 b.

In the embodiment, as illustrated in FIGS. 2 and 3, the respectiveguiding flow passages 24 of the header portions (21 a, 21 b, 21 c, and21 d) include the guiding flow passages 24 a and 24 c corresponding tothe plurality of entrance openings 15 a and the guiding flow passages 24b and 24 d corresponding to the plurality of exit openings 15 b. Thatis, the guiding flow passage 24 a corresponds the entrance openings 15 aof the first flow passages 1 a. The guiding flow passage 24 bcorresponds the exit openings 15 b of the first flow passages 1 a. Theguiding flow passage 24 c corresponds the entrance openings 15 a of thesecond flow passages 1 b. The guiding flow passage 24 d corresponds theexit openings 15 b of the second flow passages 1 b.

In the embodiment, the plurality of flow passages 25 (25 a and 25 b)each are configured to guide a fluid between the plurality of core endopenings 14 and the tank 23 while changing a flow passage sectionalshape orthogonal to the flow direction of fluids (fuel 4 and oil 5).That is, the respective flow passages 25 (25 a and 25 b) each connectthe core end openings 14 to the tank 23 while changing the flow passagesectional shape. In this specification, “changing the flow passagesectional shape” means changing at least one of a flow passage height, aflow passage width, or a geometric shape (including a rectangle, asquare, and a circle) of the flow passage section.

The flow passages 25 have core side openings 26 (refer to FIG. 7)disposed at the X2-direction side end portions and tank side openings 27(refer to FIG. 8) disposed at the X1-direction side end portions, asillustrated in FIG. 6. The flow passages 25 each are provided as a pairwith the corresponding core end opening 14. That is, the core sideopenings 26 a of the flow passages 25 a are connected to thecorresponding core end openings 14 a (refer to FIG. 2). The core sideopenings 26 b of the flow passages 25 b are connected to thecorresponding core end openings 14 b (refer to FIG. 3). In FIG. 7, acore side end portion 2 a of the header 2 is illustrated with a hatchingfor convenience.

The respective flow passages 25 of the guiding flow passages 24 havedifferent positions in the Y-direction since connection points (entranceopenings 15 a and exit openings 15 b of first flow passages 1 a, andentrance openings 15 a and exit openings 15 b of second flow passages 1b) are different from each other, and are formed such that theY1-direction side and the Y2-direction side are substantially symmetricin the Y-direction. Each of the flow passages 25 has a common basicstructure except the difference described above. Hereinafter, connectionpoints of the flow passages 25 will be simply referred to as the “coreend openings 14”, and a structure common to the respective flow passages25 a and 25 b will be described except when the necessity arises.

As illustrated FIG. 6, the tank side openings 27 of the flow passages 25are open to the inside of the tanks 23. Flow passage end surfaces 251 ona tank 23 side of the guiding flow passages 24 in which the tank sideopenings 27 are formed (refer to FIGS. 2, 3, and 5) are obliquelyinclined in an XY-plane with respect to the X-direction and theY-direction. In addition, the flow passage end surfaces 251 are smoothlyconnected to the inside surfaces of the tanks 23. The Y-directiondimensions of the inclined flow passage end surfaces 251 are set tosubstantially match the Y-direction dimensions of the ports 22 (flowpassage widths W2 a and W2 b). In addition, the inside surface 252 ofthe flow passages 25 (refer to FIGS. 2, 3, and 5) are formed to smoothlyconnect the inside surfaces of the core end openings 14 to the insidesurfaces of the tanks 23. In FIG. 8, the flow passage end surfaces 251appeared in the tanks 23 are illustrated with hatching in order todifferentiate from the tank side openings 27.

As illustrated in FIGS. 4 and 7, sectional shapes of the core sideopenings 26 (opening shapes) match sectional shapes of the correspondingcore end openings 14 (opening shapes). That is, the core side openings26 each have the flow passage height H1 and the flow passage width W1,which are the same as the flow passage height H1 and the flow passagewidth W1 of each of the core end openings 14. As illustrated in FIG. 8,sectional shapes of the tank side openings 27 a and 27 b (openingshapes) have flow passage heights H4 a and H4 b larger than the flowpassage height H1, and the flow passage widths W3 a and W3 b smallerthan the flow passage width W1, respectively. The sectional shapes ofthe tank side openings 27 are opening shapes in the flow passage endsurfaces 251.

In the embodiment, each of the flow passages 25 a and 25 b has a flowpassage sectional shape which changes such that the closer to a core endopening 14 side, the closer a flow passage width become to the flowpassage width W1 of each of the core end openings 14 (refer to FIG. 7),and the closer to a tank 23 side, the closer a flow passage width becometo the flow passage widths W3 a and W3 b of the boundary portions withthe tanks 23 (refer to FIG. 8), as illustrated in FIGS. 2 and 3.Specifically, each of the flow passages 25 a and 25 b is formed suchthat a flow passage width substantially decreases in a monotonic mannerfrom the flow passage widths W1 of the core end openings 14 (refer toFIG. 7) to the flow passage widths W3 a andW3 b of the tank sideopenings 27 (refer to FIG. 8).

In addition, in the embodiment, each of the flow passages 25 has a flowpassage sectional shape which changes such that the closer to the coreend opening 14 side, the closer a flow passage height become to the flowpassage height H1, and the closer to the tank 23 side, the closer a flowpassage height become to the flow passage height H3, as illustrated inFIG. 9. Specifically, each of the flow passages 25 is formed such that aflow passage height substantially increases in a monotonic manner fromthe flow passage height H1 of the core side opening 26 (core end opening14) to the flow passage heights H4 a and H4 b of the tank side openings27. The flow passage heights H4 a and H4 b are heights between the flowpassage height H1 and the flow passage height H3 (H3>H4 a and H4 b>H1).That is, the flow passage heights of the flow passages 25 b illustratedin FIG. 9 are enlarged such that the more the flow passages protrudetoward a flow passage 25 a side adjacent to the Z-direction the closerto the tank side openings 27.

More specifically, since the first flow passages 1 a and the second flowpassages 1 b are alternately stacked in the Z-direction, the flowpassages 25 b that communicate with the second flow passages 1 b and theflow passages 25 a that communicate with the first flow passages 1 a areadjacent to each other in the Z-direction, and each flow passage isdefined by bulkheads 253 and a flow passage end surface 251. For thisreason, the flow passages 25 a are blocked without openings due to theflow passage end surfaces 251 of the flow passages 25 b, in which thetank side openings 27 b are formed. In other words, the plurality oftank side openings 27 (27 a or 27 b) are arranged in the flow passageend surfaces 251 in the Z-direction at intervals equivalent to one layerof the first flow passages 1 a or the second flow passages 1 b stackedin the Z-direction. For this reason, each of the flow passages 25 isformed by enlarging a flow passage height such that an interval betweenthe adjacent tank side openings 27 in the Z-direction is smaller than aninterval equivalent to one layer of the flow passage unit (H1+thicknessof tube plate 12). Although not illustrated, the same applies to theflow passages 25 a.

In the embodiment, the flow passages 25 each are formed such that aratio between a flow passage width and a flow passage height of a flowpassage sectional shape (aspect ratio) is changed while a flow passagesectional area is kept substantially constant in the flow direction of afluid. For example, as in FIG. 10 in which the flow passages 25 b areconceptually illustrated, the flow passages 25 b each have the flowpassage width W1 and the flow passage height H1 in the core side opening26 and have the flow passage width W3 b (<W1) and the flow passageheight H4 b (>H1) in the tank side opening 27. The opening area of eachcore side opening 26 (flow passage width W1×flow passage height H1) issubstantially the same as the opening area of each tank side opening 27(flow passage width W3 b×flow passage height H4 b). In addition, theflow passages 25 each are formed such that a flow passage sectional areathereof in a direction orthogonal to the flow direction of a fluid (oil5) is kept substantially constant even in a middle portion between thecore side opening 26 and the tank side opening 27.

Therefore, the flow passages 25 each have a flow passage sectional shapewhich is a horizontally long (wide) shape matching the core end opening14 in the core side opening 26, and have an aspect ratio of the section(ratio between a flow passage width and a flow passage height) thatchanges such that the closer to the tank side opening 27, the smallerthe flow passage width and the larger the flow passage height. As aresult, the tank side openings 27 of the flow passages 25 each have ashape close to a vertically long shape narrower than the core sideopening 26, and have a sectional shape close to the sectional shape ofthe tank 23 illustrated in FIG. 8. Although not illustrated, the sameapplies to the flow passages 25 a.

In the embodiment, as described above, in total, four header portions(21 a, 21 b, 21 c, and 21 d) are formed in a single header 2, by meansof the three-dimensional modelling technology (so-called 3D printer).The header 2 is formed, for example, by means of a powder laminationmolding method in which a powdery material is irradiated with a laser oran electronic beam to be melted or sintered. The same material as thecore 1 can be used as a material of the header 2, and for example, analuminum alloy, stainless steel (SUS), a titanium alloy, and a nickelalloy can be used.

Next, a joining portion between the end surface 11 of the core 1 and theheader 2 will be described.

As illustrated in FIG. 7, the appearance of the core side end portion 2a (hatching portion) of the header 2 has the same rectangular shape asthe appearance of the end surface 11 (refer to FIG. 4) of the core 1. Anedge 28 configuring the appearance shape of the header 2 and thebulkheads 253 defining the respective flow passages 25 of the guidingflow passages 24 are exposed to the core side end portion 2 a. In thecore side end portion 2 a, the edge 28 has a rectangular shape and thebulkheads 253 are formed in a lattice shape.

In the embodiment, the edge 28 (refer to FIG. 7) of the header 2 isjoined to an edge of the end surface 11 (refer to FIG. 4) of the core 1,and the respective bulkheads 253 (refer to FIG. 7) of the plurality offlow passages 25 of the header 2 are joined to core end surface portions12 a (refer to FIG. 4) of the tube plates 12 between the first flowpassages 1 a and the second flow passages 1 b.

The edge 28 of the header 2 is joined to the side plates 13, end surfaceportions of the side bars 16, and Y-direction end portions of the coreend surface portions 12 a of the tube plates 12, of the end surface 11of the core 1. The bulkheads 253 of the header 2 are joined to the coreend surface portions 12 a of the tube plates 12 and the end surfaceportions of the partitioning members 18, of the end surface 11 of thecore 1. In other words, the header 2 is joined to the core 1 with thesubstantially entire end surface region, except for the core endopenings 14 formed in the end surface 11 of the core 1, as a joiningregion.

In the embodiment, the header 2 is directly formed on the end surface 11of the core 1 by the 3D printer described above which adopted thethree-dimensional modelling technology. That is, first, the assembly ofthe core 1 on which the side plates 13, the side bars 16, thepartitioning members 18, the corrugated fins 19, and the tube plates 12are stacked is joined by brazing, and thus the core 1 is formed. Afterthen, by the header 2 being directly modelled on the end surface 11 ofthe core 1, the header 2 is configured.

(Header for U-Turn Flow)

As illustrated in FIGS. 2 and 3, the header for U-turn flow 3 isprovided on the core 1 to cover the openings for U-turn flow 17 of thecore 1, and has a flow passage for U-turn flow 31. The flow passage forU-turn flow 31 has a substantially semicircular shape, and is providedso as to correspond to each of the first flow passages 1 a and thesecond flow passages 1 b. Accordingly, a fluid flowed into the flowpassage for U-turn flow 31 from one of the openings for U-turn flow 17(exit portions 17 a) flows in a substantially semicircle along the flowpassage for U-turn flow 31 to make a U-turn, and flows into the otherone of the openings for U-turn flow 17 (entrance portions 17 b).

Effects of the Embodiment

In the heat exchanger 100 of the embodiment, the following effects canbe obtained.

In the heat exchanger 100 of the embodiment, as described above, theheader portions 21 a and 21 b are provided with the guiding flowpassages 24 a and 24 b, which are connected to the plurality of core endopenings 14 a of the first flow passages 1 a and have the plurality offlow passages 25 a extending to the corresponding tank 23 side,respectively. The header portions 21 c and 21 d are provided with theguiding flow passages 24 c and 24 d, which are connected to theplurality of core end openings 14 b of the second flow passages 1 b andhave the plurality of flow passages 25 b extending to the correspondingtank 23 side, respectively. The plurality of flow passages 25 (25 a and25 b) each are configured to guide a fluid between the plurality of coreend openings 14 and the tank 23 while changing a flow passage sectionalshape orthogonal to the flow direction of a fluid. Accordingly, the heatexchanger 100 of the embodiment can set flow passage sectional shapes ofthe plurality of flow passages 25 of flow passage guiding units 24regardless of the flow passage sectional shapes of the core end openings14, and can guide fluids (fuel 4 and oil 5) between the tanks 23 and thecore 1 via each of the flow passages 25. That is, the flow passagesectional shapes of the plurality of flow passages 25 of the flowpassage guiding units 24 can be changed to become closer to a flowpassage sectional shape on the tank 23 side as becoming closer to thetank 23 side. In addition, the flow passage sectional shapes of the flowpassages 25 of the flow passage guiding units 24 can be changed tobecome closer to the shapes of the core end openings 14 as becomingcloser to the core end opening 14 side. As a result, since a change inthe flow passage sectional shape between the core end openings 14 a and14 b of the first flow passages 1 a and the second flow passages 1 b andthe header 2 (tanks 23) can be made moderate, the heat exchanger 100 ofthe embodiment can suppress an increase in a pressure loss of a fluidwhen the fluid flows into the heat exchanger 100 or flows out from theheat exchanger 100 via the header 2.

In addition, by a header 23 being provided with the guiding flowpassages 24 having the plurality of flow passages 25, it is notnecessary to provide a flow passage structure, of which the sectionalshape changes, on a core 1 side. As a result, the heat exchanger 100 ofthe embodiment can adopt the core 1 having a simple shape, and cansuppress the structure of the core 1 becoming complicated.

In the heat exchanger 100 of the embodiment, as described above, theflow passages 25 (25 a and 25 b) each are formed to have a flow passagesectional shape which changes such that as the closer to the core endopening 14 (14 a and 14 b) side, the closer the flow passage widthbecomes to the flow passage width W1 of the core end opening, and thecloser to the tank 23 (23 a and 23 b) side, the closer the flow passagewidth becomes to the flow passage widths W3 a and W3 b of the boundaryportions between the flow passage guiding units 24 and the tanks 23.Accordingly, by changing the flow passage widths of the flow passages25, a change in a flow passage width between the header 2 (tanks 23) andthe core end openings 14 can be made moderate. As a result, the heatexchanger 100 of the embodiment can suppress an increase in the pressureloss caused by a sudden change in the flow passage widths of theboundary portions between the header 2 (tanks 23) and the core endopenings 14.

In the heat exchanger 100 of the embodiment, as described above, theflow passages 25 (25 a and 25 b) each are formed to have a flow passagesectional shape which changes such that the closer to the core endopening 14 (14 a and 14 b) side, the closer the flow passage heightbecomes to the flow passage height H1 of the core end opening, and thecloser to the tank 23 (23 a and 23 b) side, the closer the flow passageheight becomes to the flow passage height H3 of each of the boundaryportions between the flow passage guiding units 24 and the tanks 23.Accordingly, by changing the flow passage heights of the flow passages25, a change in the flow passage height between the header 2 (tanks 23)and the core end openings 14 can be made moderate. As a result, the heatexchanger 100 of the embodiment can suppress an increase in the pressureloss caused by a sudden change in the flow passage height of a boundaryportion between the header 2 (tanks 23) and the core end openings 14.

In the heat exchanger 100 of the embodiment, as described above, theflow passages 25 each are formed such that a ratio between a flowpassage width and a flow passage height of a flow passage sectionalshape is changed while a flow passage sectional area is keptsubstantially constant in the flow direction of a fluid (fuel 4 and oil5). Accordingly, even in a case where the flow passage widths or theflow passage heights of the flow passages 25 are changed according tothe shapes of the core end openings 14 and the flow passage sectionalshapes on the tank 23 side, it is not necessary to change the flowpassage sectional area of each of the flow passages 25 to become larger.As a result, the heat exchanger 100 of the embodiment can suppress anincrease in the pressure loss caused by a change in the flow passagesectional areas of the flow passages 25.

In the heat exchanger 100 of the embodiment, as described above, theheader portions 21 a and 21 b and the header portions 21 c and 21 d areintegrally provided in the common header 2. The guiding flow passages 24a and 24 b having the plurality of flow passages 25 a for guiding afluid flowing into or flowing out from the plurality of first flowpassages 1 a and the guiding flow passages 24 c and 24 d having theplurality of flow passages 25 b for a fluid flowing into or flowing outfrom the plurality of second flow passages 1 b are provided in thecorresponding header portions 21 a to 21 d, respectively. Accordingly,even in a case where the core end openings 14 a of the first flowpassages 1 a and the core end openings 14 b of the second flow passages1 b are formed in the common end surface 11 of the core 1, the header 2can be used in common. As a result, since the internal volume of theheader 2 can be decreased compared to a case where the header 2 isseparately provided from the first flow passages 1 a and the second flowpassages 1 b, the heat exchanger 100 of the embodiment can suppress thetotal weight (wet weight) of the heat exchanger 100, in particular, in acase where liquid fluids (fuel 4 and oil 5) are used. This isparticularly useful in application of strict weight limits of anaircraft as in the embodiment. In addition, even in a case where theheader 2 is used in common to the first flow passages 1 a and the secondflow passages 1 b, the suppression of a pressure loss can be achieved bychanging the flow passage sectional shape of each of the flow passages(25 a and 25 b) of the guiding flow passages (24 a, 24 b, 24 c, and 24d).

In the heat exchanger 100 of the embodiment, as described above, theheader portions 21 a and 21 b that cover the entrance openings 15 a andthe exit openings 15 b of the first flow passages 1 a (core end openings14 a) respectively are provided with the guiding flow passages 24 a and24 b respectively. In addition, the header portions 21 c and 21 d thatcover the entrance openings 15 a and the exit openings 15 b of thesecond flow passages 1 b (core end openings 14 b) respectively areprovided with the guiding flow passages 24 c and 24 d respectively.Accordingly, even in a case where both of the entrance openings 15 a andthe exit openings 15 b are formed in the common end surface 11 of thecore 1, the header 2 can be used in common due to the guiding flowpassages 24 a and 24 c corresponding to the entrance openings 15 a andthe guiding flow passages 24 b and 24 d corresponding to the exitopenings 15 b. As a result, the total weight (wet weight) of the heatexchanger 100 of the embodiment can be suppressed compared to a casewhere the header 2 is separately provided from the entrance openings 15a and the exit openings 15 b. In addition, even in a case where theheader 2 is used in common, the heat exchanger 100 of the embodiment canachieve the suppression of a pressure loss by changing the flow passagesectional shape of each of the flow passages (25 a and 25 b) of theguiding flow passages 24 a and 24 c and the guiding flow passages 24 band 24 d.

In the heat exchanger 100 of the embodiment, as described above, theedge 28 of the header 2 is joined to an edge of the end surface 11 ofthe core 1, and the respective bulkheads 253 of the plurality of flowpassages 25 of the header 2 are joined to core end surface portions 12 aof the tube plates 12 between the first flow passages 1 a and the secondflow passages 1 b. Accordingly, the core 1 and the header 2 can bejoined not only to the edges but also to an outer surface where the coreend openings 14 (core end surface portions 12 a of tube plates 12) arenot formed, in the end surface 11 in which the core end openings 14 areformed. As a result, since a joining area can be increased and a regionbetween both ends of the end surface 11 of the core 1 in the Y-directioncan be set as a joining region, the heat exchanger 100 of the embodimentcan effectively improve the joining strength of the core 1 and theheader 2. In addition, since the pressure resistance performance of theheader 2 can be improved with the improvement of the joining strengthand the degree of freedom of internal structure of the header 2 can beenhanced, the heat exchanger 100 of the embodiment can easily optimizethe shapes of the flow passages 25 and the tanks 23 of the header 2.

In the heat exchanger 100 of the embodiment, as described above, therespective core end openings 14 a and 14 b of the plurality of firstflow passages 1 a and the plurality of second flow passages 1 b arevertically arranged in the end surface 11 of the rectangularparallelepiped core 1. The header 2 is joined to the end surface 11 soas to collectively cover the respective core end openings 14 of theplurality of first flow passages 1 a and the plurality of second flowpassages 1 b. Accordingly, since the core 1 can be formed in arectangular parallelepiped shape just as a general stacked heatexchanger, it can be suppressed that the structure of the core 1 becomescomplicated. In addition, since the flow passages 25 of the guiding flowpassages 24 can distribute (guide) a fluid to the first flow passages 1a and the second flow passages 1 b, it is not necessary to form therespective core end openings 14 of the plurality of first flow passages1 a and the plurality of second flow passages 1 b at positions separatedaway from each other in order to mount another header 2. As a result,the heat exchanger 100 of the embodiment can simplify the structure ofthe core 1.

It is to be considered that the embodiment disclosed herein is merely anexample in all respects and does not limit the invention. The scope ofthe invention is described in the Claims not in the embodiment describedabove, and includes all modifications (modification examples) within thesame meaning and scope of the Claims.

For example, although an example of a plate-fin heat exchanger is givenin the embodiment, the invention is not limited thereto. In theinvention, for example, the invention may be applied to a shell and tubetype heat exchanger. In the invention, any type of heat exchanger may beadopted insofar as a heat exchanger has the structure of distributing afluid to a plurality of core end surface openings from a header.

In addition, although an example of the heat exchanger 100 that ismounted on an aircraft and exchanges heat between fuel for an aircraftand oil for an aircraft (lubricating oil) is given in the embodiment,the invention is not limited thereto. In the invention, the type of afluid may be any fluid other than fuel and oil. A fluid may be a gas ora liquid.

Although an example in which the first flow passages and the second flowpassages are provided to exchange heat between two types of fluids isgiven in the embodiment, the invention is not limited thereto. In theinvention, three or more types of flow passage units may be provided toexchange heat among three or more types of fluids.

Although an example in which the four header portions (21 a, 21 b, 21 c,and 21 d) having the guiding flow passages 24 are formed in a singleheader 2 is given in the embodiment, the invention is not limitedthereto. One to three header portions may be provided in the header. Forexample, each of a header having two header portions corresponding to anentrance opening and an exit opening of the first flow passages 1 a anda header having two header portions corresponding to an entrance openingand an exit opening of the second flow passages 1 b may be provided.Four headers each having one header portion may be provided.

Although an example in which three headers for U-turn flow 3 that causea fluid flowed out from the core 1 to make a U-turn and return to thecore 1 is given in the embodiment, the invention is not limited thereto.In the invention, the header for U-turn flow may not be provided. U-turnportions may be provided at the first flow passages and the second flowpassages inside the core 1. In addition, a fluid may not make a U-turn.In this case, the headers 2 may be provided instead of the headers forU-turn flow 3, one header in the X-direction may be set as an entranceside, and the other header in the X-direction may be set as an exitside.

Although an example of a counter-flow heat exchanger in which the fuel 4and the oil 5 flow in opposite directions is given in the embodiment,the invention is not limited thereto. In the invention, a parallel flowheat exchanger in which fuel and oil flow in the same direction or across-flow heat exchanger in which fuel and oil flow in directionsorthogonal to each other may be adopted.

Although an example in which the flow passage width and the flow passageheight of each of the plurality of flow passages 25 of the guiding flowpassages 24 are changed in the flow direction of a fluid is given in theembodiment, the invention is not limited thereto. In the invention, bychanging any one of the flow passage width or the flow passage height ofeach of the plurality of flow passages 25, the other one may not bechanged. For example, in FIGS. 9 and 10, the flow passage heights of theplurality of flow passages 25 may be kept constant at H1 to change flowpassage widths. The flow passage widths of the plurality of flowpassages 25 may be kept constant at W1 to change flow passage heights.

Although an example in which the flow passages 25 each are formed suchthat a flow passage sectional area is kept substantially constant in theflow direction of a fluid and a ratio between a flow passage width and aflow passage height of a flow passage sectional shape (aspect ratio) ischanged is given in the embodiment, the invention is not limitedthereto. In the invention, the flow passage sectional areas of the flowpassages may be changed.

Although an example in which separate first flow passages 1 a areindependently provided without being connected to other first flowpassages from the entrance openings 15 a to the exit openings 15 b isgiven in the embodiment, the invention is not limited thereto. In theinvention, as illustrated in FIG. 11, a mixing header 101 for causingthe plurality of first flow passages 1 a to communicate with each otherfrom the entrance openings 15 a to the exit openings 15 b may beprovided. At this time, a guiding flow passage 102 having a plurality offlow passages may be formed in the mixing header 101. The mixing header101 is provided to cover openings 103 formed in the middle of therespective first flow passages 1 a, and stirs a fluid flowed into themixing header 101 via core side openings 104 (hatching portion) toreturn to each of the first flow passages 1 a. In this case, theplurality of flow passages of the guiding flow passage 102 may beconfigured to change flow passage sectional shapes to guide a fluid suchthat for example, spiral flow (swirl or tumble) occurs inside the mixingheader 101. Accordingly, temperature unevenness in the respective firstflow passages 1 a can be reduced. The same applies to the second flowpassages 1 b.

Although an example in which the header 2 is directly formed (modelled)on the end surface 11 of the core 1 by means of the three-dimensionalmodelling technology is given in the embodiment, the invention is notlimited thereto. In the invention, the header may be separatelymanufactured from the core and be joined to the core by brazing.

In addition, although an example in which the core end surface portions12 a of the tube plates 12 on the end surface 11 of the core 1 arejoined to the bulkheads 253 of the header 2 is given in the embodiment,the invention is not limited thereto. In the invention, the edge of theend surface 11 of the core 1 may be joined to the edge 28 of the coreside end portion 2 a of the header 2 by welding, and may not be joinedto an inside region (bulkheads 253) of the end surface 11.

DESCRIPTION OF REFERENCE NUMERALS

-   -   1 core    -   1 a first flow passage    -   1 b second flow passage    -   2 header    -   2 a edge    -   4 fuel (fluid)    -   5 oil (fluid)    -   11 end surface    -   12 tube plate (partition plate)    -   12 a core end surface portion    -   14 (14 a, 14 b) core end opening    -   15 a entrance opening    -   15 b exit opening    -   21 a, 21 b header portion (first header portion)    -   21 c, 21 d header portion (second header portion)    -   22 (22 a, 22 b) port    -   23 (23 a, 23 b) tank    -   24 a guiding flow passage (first guiding flow passage, entrance        guiding flow passage)    -   24 b guiding flow passage (first guiding flow passage, exit        guiding flow passage)    -   24 c guiding flow passage (second guiding flow passage, entrance        guiding flow passage)    -   24 d guiding flow passage (second guiding flow passage, exit        guiding flow passage)    -   25 (25 a, 25 b) flow passage    -   100 heat exchanger    -   253 bulkhead    -   W1 flow passage width (first flow passage width)    -   W2 a, W2 b flow passage width (second flow passage width)    -   H1 flow passage height (first flow passage height)    -   H2 a, H2 b flow passage height (second flow passage height)

1. A heat exchanger comprising: a core that includes a plurality offirst flow passages and a plurality of second flow passages andexchanges heat between fluids flowing in the first flow passages and thesecond flow passages respectively; and a header that includes a firstheader portion, which is connected to an end surface of the core andcovers core end openings of the plurality of first flow passages, and asecond header portion, which covers core end openings of the pluralityof second flow passages, wherein the first header portion and the secondheader portion each include a port for causing the fluids to flow intoor flow out from an inside thereof and a tank connected to the port, andat least one of the first header portion or the second header portionincludes a guiding flow passage that is connected to the plurality ofcore end openings of one of the first flow passages or the second flowpassages and that has a plurality of flow passages which extend to acorresponding tank side and guide the fluids between the plurality ofcore end openings and the tank while changing a flow passage sectionalshape orthogonal to a flow direction of the fluids.
 2. The heatexchanger according to claim 1, wherein the plurality of core endopenings each have a first flow passage width in a width directionorthogonal to a flow passage height direction, in a section orthogonalto the flow direction of the fluids, the tank has a second flow passagewidth smaller than the first flow passage width in the width direction,in a boundary portion of the tank with the guiding flow passage, and theflow passages each have the flow passage sectional shape which changessuch that the closer to a core end opening side, the closer a flowpassage width becomes to the first flow passage width, and the closer tothe tank side, the closer the flow passage width becomes to the secondflow passage width.
 3. The heat exchanger according to claim 1, whereinthe plurality of core end openings each have a first flow passage heightin a flow passage height direction, in a section orthogonal to the flowdirection of the fluids, the tank has a second flow passage heightlarger than the first flow passage height in the flow passage heightdirection, in a boundary portion of the tank with the guiding flowpassage, and the flow passages each have the flow passage sectionalshape which changes such that the closer to the core end opening side,the closer a flow passage height becomes to the first flow passageheight, and the closer to the tank side, the closer the flow passageheight becomes to the second flow passage height.
 4. The heat exchangeraccording to claim 1, wherein the flow passages each are formed suchthat a ratio between a flow passage width and a flow passage height ofthe flow passage sectional shape is changed while a flow passagesectional area is kept substantially constant in the flow direction ofthe fluids.
 5. The heat exchanger according to claim 1, wherein thefirst header portion and the second header portion are integrallyprovided in the common header, and the guiding flow passage includes afirst guiding flow passage having the plurality of flow passages forguiding the fluids flowed into or flowed out from the plurality of firstflow passages and a second guiding flow passage having the plurality offlow passages for guiding the fluids flowed into or flowed out from theplurality of second flow passages.
 6. The heat exchanger according toclaim 1, wherein the core end openings of the first flow passages andthe core end openings of the second flow passages each include aplurality of entrance openings and a plurality of exit openings formedin the end surface of the core, and the guiding flow passage provided inat least one of the first header portion covering the first flowpassages or the second header portion covering the second flow passagesincludes an entrance guiding flow passage corresponding to the pluralityof entrance openings and an exit guiding flow passage corresponding tothe plurality of exit openings.
 7. The heat exchanger according to claim1, wherein the core has a stacked structure in which the plurality offirst flow passages and the plurality of second flow passages arealternately stacked in a height direction via partition plates, and anedge of the header is joined to an edge of the end surface of the core,and respective bulkheads of the plurality of flow passages of the headerare joined to core end surface portions of the partition plates betweenthe first flow passages and the second flow passages.
 8. The heatexchanger according to claim 1, wherein the core has a rectangularparallelepiped shape, and the respective core end openings of theplurality of first flow passages and the plurality of second flowpassages are vertically arranged in the end surface formed of any one ofside surfaces of a rectangular parallelepiped, and the header is joinedto the end surface so as to integrally include the first header portionand the second header portion and to collectively cover the respectivecore end openings of the plurality of first flow passages and theplurality of second flow passages.